Easy-opening container closure



0 United States Patent ul13,545,638

[72] inventor Omar L. Brown [50] Field of Search 215/465, Dayton, Ohio42; 220/54, 27; 222/54] [2!] Appl. No. 862,566 [22] Filed July 30, 1969References Clted Division of Ser. No. 696,902, Jan. i, 1968. UNITEDSTATES PATENTS Pate"! 3,435,196- 3,247,997 4/l966 Bozek 220/54 1Patented 8, 3,494,501 2/1970 Brown 220/54 [73] Assignee Ermal C. FrazeDayton, o Primary Examiner-George T. Hall by meme assignmemsAttorney-Smyth, Roston & Pavltt ABSTRACT: This disclosure describes adual cap closure as- [54] f f g F ET CLOSURE sembly for use on the opentop of a container. The outer cap is 6 C 8 rawmg scored to form aremovable tear strip to permit the removal [52] 11.8. CI 215/46, anddiscarding of the outer cap. The outercap has an end wall 220/54 and aperipheral wall and the scoring operation is carried out [5!] int. Cl865d 43/02, on the outer cap after the cap has been formed to definesuch B65d 17/24 end wall and peripheral wall.

PATENTEU DEE 8197B SHEET 1 OF 2 Arron/v6) EASY-OPENING CONTAINER CLOSUREThis application is a division of application Ser. No. 696,902, filedJan. 10, 1968, now U.S. Pat. No. 3,485,196.

BACKGROUND OF THE INVENTION It is known to use an easy-opening dual capclosure assembly to seal the open top of a container. Such closureassembly typically includes a metal outer cap and a plastic insert orinner cap within the outer cap or a sealing agent may be used in lieu ofthe plastic insert. The outer cap has a line of weakness therein forminga removable tear strip and a tab is attached to, or integral with, thetear strip for the purpose of removing the tear strip. With the tearstrip removed, the entire outer cap can be removed and discarded, andthereafter, the inner cap alone is used as a removable closure element.

This type of closure assembly can be used, for example, on a glass jar,bottle, or a special metal can and is particularly adapted for use onthe container of a product which is not ordinarily entirely consumedshortly following the opening of the container. The entire closureassembly remains on the product until the consumer desires to use samewhereupon the outer closure is removed as described above, andthereafter, the inner cap serves as a reusable closure for thecontainer.

The metal outer cap typically has an end wall which closes the openingof the container and a peripheral wall or flange transverse to the endwall for gripping a portion of the container wall adjacent the openingto secure the closure assembly to the container. The outer cap is scoredto form a line of weakness which extends from the peripheral wall overthe end wall to define the tear strip. A tab for removal of the tearstrip may be formed integrally with the outer cap or formed separatelyand then attached to the tear strip.

A very difficult problem arises in the scoring of the metal outer cap toform the tear strip. According-to the prior art method, the scoringoperation isiperforrned-in the flat. That is, the closure blank isscored while the blank is in a flat condition and prior to the time thatit is shaped to form the peripheral wall. Following the scoringoperation, the blank is deformed or bent to form the end wall and theperipheral wall. As the line of weakness extends from the end wall tothe peripheral wall, such deformation or bending also bends the materialof Y the outer cap along the line-of weakness. This bending of theprescored metal has resulted in fracturing of the outer cap along theline of weakness adjacent the bend portion which integrally joins theend wall and peripheral wall when the flat blank is bent in this manner,the material of the peripheral flange adjacent the bend portion isforced and squeezed together circumferentially because of the inherentnature of forming the generally cylindrical peripheral flange at rightan gles to the end wall. Simultaneously, at least some of the materialof the bend portion is radially stretched. As the cap is weakest alongthe line of weakness, it deforms along the line of weakness under theinfluence of these forces and not infrequently completely fractures.This problem is further aggravated when the peripheral wall is rolled todeform the peripheral wall to secure the closure assembly to thecontainer. Generally the results of scoring in the flat and then bendingthe blank to form the outer cap are quite erratic. In other instances,the squeezing together of the metal adjacent the bend portion along theline of weakness fractures or nearly fractures the metal and also causesthe edges of the tear strip to be overlapped by the adjacent portions ofthe outer cap. This captivates the tear strip and makes removal thereofmuch more difficult.

SUMMARY OF THE INVENTION The present invention eliminates the problemheretofore experienced with scoring'of the blank for the outer cap. Inparticular, the present invention teaches that the outer cap blankshould be bent to form the outer cap which has an end wall and aperipheral wall and then the outer cap should be scored. By scoring theend wall and the peripheral wall rather than scoring in the flat, theproblem of fracture of the outer cap along the line of weakness andcaptivating of the cap are eliminated. Furthermore, the results of thescoring operation .are not erratic and well-controlled results areobtained.

When the outer cap is formed, the end wall and the peripheral wall areinterconnected by an integral bend portion having a relatively smallradius. The score line or line of weakness formed in the scoringoperation extends at least substantially continuously from theperipheral wall over a portion of the end wall to define a tear stripwhich is at least partially removable from the remainder of the outercap. The scoring need not be completely continuous at the bend portion,because the metal can be relatively easily torn around such bend portioneven without the benefit of a continuous score line. Y

The present invention is applicable to the scoring of an outer cap inany manner that results in scoring on both the end wall and theperipheral wall and is particularly applicable to scoring of outer capsof the type described and claimed in application Ser. No. 599,124 thesubject matter of which is incorporated by reference herein. Preferably,however, the line of score begins on the peripheral wall and extends atleast substantially continuously from an initial point at or closely adjacent the outer edge of the peripheral wall to an area on the end walla substantial distance from such point and then back to the peripheralwall to terminate at a location on the peripheral wall which is close tothe initial point. Preferably, the tear strip extends at leastsubstantially completely across the end wall and the score lineterminates at a location which is spaced from the outer edge so that atear strip along one side thereof is not completely separable from theouter cap so that the outer cap may be removed as a complete integralunit.

As the scoring operation is performed after the formation of the outercap, it is important to assure that the portion of the line of weaknesson the end wall will be properly oriented with respect to the portion ofthe line of weakness on the peripheral wall. Preferably such portions ofthe score line should be alined. To assure that this alinement isobtained, the present invention teaches scoring of the end wall and ofthe peripheral wall at the same work station without substantiallymoving the outer cap. If the cap is maintained stationary, the scorescan be alined without the need' for providing special indexing means inmoving the outer cap from one scoring station to another. To furtherassure that the portions of the line of weakness are properly alined andto increase the speed of the process, it is preferred to score the endwall and the peripheral wall substantially simultaneously. Theperipheral wall may be scored last, if desired, and the peripheral wallmay be scored at a separate station if appropriate indexing means areprovided.

The scoring operation can be advantageously carried out by positioningthe outer cap over a support member and then engaging the end wall andthe peripheral wall with first and second movable scoring tools,respectively. The second scoring tool for scoring the peripheral wallcan advantageously be moved generally radially of the cap as by apivoting motion.

The concepts of the present invention can be applied to any outer caphaving an end wall and a peripheral wall and is not dependent upon theattachment of a tab to the tear strip in any particular manner. Thus,the tab may be integral with the tear strip or may be formed separatelyand suitably affixed thereto as by a rivet formed integrally with theouter cap. In the preferred practice of this invention, a rivet isformed integral with the end wall and such rivet is preferably formed atany time prior to the scoring operation. Following the scoringoperation, an insert or inner cap which is preferably constructed of aresilient material such as plastic is inserted within the cap. Theclosure assembly can then be positioned over an opening in a containerwith the end wall covering such open ing, and the peripheral wall isrolled or otherwise formed to grip the surface of the container adjacentthe opening to secure the closure assembly to the container.

Another problem with the outer caps of this type is to prevent the tearstrip from tearing completely out of the cap.

To prevent this from happening, the present invention teaches graduallydecreasing the depth of the score adjacent the end thereof whichterminates at a location spaced from the outer periphery of the cap.

The invention, both as to its organization and method of operationtogether with further features and advantages thereof may best beunderstood by reference to the following description taken in connectionwith the accompanying draw- BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 isa top plan view of a closure blank having a rivet formed integrallytherewith.

FIG. 2 is a top plan view of the closure blank after the peripheralregion thereof has been bent downwardly to form the peripheral wall tothereby convert the blank into the outer cap.

FIG. 3 is a top plan view similar to FIG. 2 following the scoringoperation on the outer cap.

FIG. 4 is a sectional view illustrating the scoring operation.

FIG. Sis a plan view taken along line 5-5 of FIG. 4 and illustrating oneform of scoring tool for scoring the peripheral wall.

FIG. 6 is a front elevational view taken generally along line 6-6 ofFIG. 5 with the outer cap removed and illustrating the scoring tool.

FIG. 7 is an elevational view taken along line 7-7 of FIG. 3 and showingthe outer cap afterthe scoring operation has been performed thereon. 4

FIG. 7a is a sectional view taken along line 7a-7a of FIG. 7 and showingone segment of the line of weakness on the peripheral wall.

FIG. 8 is a top plan view of the outer cap after a tab has been secured.to the tear strip and following the insertion of the inner cap therein.

FIG. 9 is a sectional view taken along line 9-9 of FIG. 8 andillustrating the entire closure assembly secured to the open end of acontainer.

FIG. 9a is a fragmentary sectional view of a peripheral region of aslightly modified closure assembly on an open end of a container.

FIG. 10 is an enlarged fragmentary elevational view taken along line10-10 of FIG. 8 and showing one of the score line segments on theperipheral wall.

FIG. 11 is a sectional view taken along line 11-11 of FIG. 10.

FIG. 12 is an enlarged fragmentary elevational view taken along line12-12 of FIG. 8 and showing the other score line segment on theperipheral wall.

FIG. 13 is a fragmentary sectional view taken along line 13-13 ofFIG.12.

DESCRIPTION OF THE PREFERRED EMBODIMENTS Referring to the drawings andin particular to FIGS. 1-3 thereof reference numeral 15 designates anouter cap blank constructed of aluminum sheet metal or of other suitablematerial. Preferably, the first step of the operation is to form ahollow rivet 17 integral with the blank 15 by any suitable known method.Secondly, a peripheral region of the outer cap blank 15 is bent toconvert the outer cap blank 15 into an outer cap or closure member 19.The bending operation converts the peripheral region of the blank 15into a peripheral wall 21 (FIG. 4) which extends generally transverselyof an end wall 23. Although the outer cap 19 may have different shapes,in the embodiment illustrated the peripheral wall 21 is generallycylindrical and the end wall 23 is circular in plan,

and the walls21 and 23 are connected by an integral bend portion 25(FIG. 4).

Next, the outer cap 19 is scored to define a line of weakness 27 whichin turn defines a tear strip 29. Although the line of weakness 27 mayassume various configurations, in the embodiment illustrated the line ofweakness 27 has two segments 31 and 33 formed in the peripheral wall 21(FIG. 7) and a generally U or V-shaped segment 35 formed in the end wall23 (FIG. 3). The segment 31 begins at an outer edge 37 of the peripheralwall and extends at least substantially completely over the peripheralwall to meet or substantially connect with the segment 35. Similarly,the segment 33 connects or substantially connects with the segment 35,but the outer end thereof is scored in a manner to stop tear-out. Forexample, the outer end may be turned upwardly to form a U and be spacedsome distance from the outer edge 37 to prevent complete separation ofthe tear strip 29 from the remainder of the cap 19 as more fullydescribed in said U.S. Pat. application Ser. No. 599,124.

As shown by way of example in FIG. 7a, the segments 33 and 35 do notinterconnect at the bend portion 25 thereby making the line of weakness27 slightly discontinuous. It will be appreciated, however,'that theline of weakness 27 can be properly characterized as substantiallycontinuous notwithstanding such slight interruptions in the score as mayoccur along the bend portion 25. Of course, the segments 33 and 35 maybe made to interconnect, if desired.

The particulars of the scoring operation and tooling are shown in FIGS.4-6. The outer cap 19 is positioned over a rigid support member 39,which conforms to the interior of the cap, so that the end wall 23 andthe peripheral wall 21 are rigidly supported thereby. With the cap 19held in this position, a first scoring tool 41 having a recess 43 toaccommodate the rivet 17, and a scoring element 45 shaped to conform tothe segment 35 of theline of weakness 27 is moved toward the end wall23. The tool 41 is moved so that the scoring element 45 thereof forciblycontacts the end wall 23 to form the segment 35 of the line of weakness27. The scoring element 45 preferably has sufficient length to extendradially outwardly along the end wall 23 to a point substantially at theperiphery of the end wall; however, it is not necessary that the scoringelement be curved adjacent the bend portion 25 to score the bendportion. It is sufficient if the scoring element 45 remains flatadjacent the bend portion 25 because once the tearing action along theline of weakness 27 is initiated, it easily progresses around the bendportion 25, even in the absence of a completely continuous score linethereon.

Next, while the cap 19 remains stationary on the support member 39, asecond scoring tool 47 is advanced toward the peripheral wall 21. Asbest seen in FIGS. 5 and 6, the scoring tool 47 has a linear scoringelement 49 and a .I-shaped scoring element 51. In the embodimentillustrated, the scoring tool 47 is pivotally mounted on a suitablysupported shaft 53 for movement by an operating rod 55 toward and awayfrom the peripheral wall 21. The scoring tool 47 is suitably curved tomatch the curve on the peripheral wall 19. The elements 49 and 51 areotherwise suitably arranged and the location of the shaft 53 isappropriately selected so that the elements 49 and 51 will besubstantially parallel to the surface areas of the peripheral wall 21which they contact at the instant of contact.

The scoring element 51 is preferably constructed so that the score line33 formed thereby will be of progressively decreasing depth as itextends toward the end thereof (FIGS. 7a and 11). To this end thescoring element 51 protrudes a progressively decreasing distance fromthe body of the scoring tool 47 as it extends toward and through thehooked end thereof as shown in FIG. 5.

Preferably, the scoring tools 41 and 47 are operated simultaneously orsubstantially simultaneously to reduce the time required for the scoringoperation. If the scoring tools 41 and 47 are operated sequentially,either of the two may be first operated. The rivet 17 may be formedwhile the blank is in the flat and is therefore very easy to work on,however, the rivet could be formed after the cap 19 is formed, ifdesired.

Next, an apertured tab 57 is placed over the rivet 17 and the latter isstaked to secure the tab to the tear strip 29 as shown in FIGS. 8 and 9.The tab may be of any suitable configuration, and in the embodimentillustrated the tab 57 is a ring tab having a nose end 59 which rests ona portion of the end wall 23 outside of the tear strip 29.

Prior to use of the cap 19, an insert or inner cap 59 (FIG. 9) ispositioned within the outer cap 19. The inner cap 59 is preferablyconstructed of a resilient material such as a plastic material which issuitable for use as a reusable removable container closurefThe inner cap59 is shaped similarly to the outer cap 19 and may terminate slightlyabove the outer edge 37 of the peripheral wall 21. The cap 19 having thetab 57 affixed thereto and the cap 59 form the closure assembly.

The closure assembly is adapted to use with a container 61 such as aglass jar or bottle or can having an opening 63 therein and a containerwall 65 surrounding the opening. The closure assembly is positioned overthe opening 63 with the end wall 23 closing the opening and with theperipheral wall 21 lying adjacent the container wall 65. The peripheralwall 21 and the corresponding portion of the inner cap 59 can then berolled or otherwise suitably'formed to securely grip the container wall65 to secure the closure assembly to the container 61. A lower region ofthe peripheral wall 21 may be rolled outwardly and upwardly into a bead66 as shown in FIG. 9 to further assist in stopping of the tearing ofthe material of the cap beyond the end of the score line segment 33.Alternatively this lower region may be folded upwardly to form a foldportion 66' as shown in FIG. 9a where corresponding parts are designatedby corresponding primed reference characters. FIGS. -13 illustrate on anenlarged scale the segments 31 and 33 of the line of weakness 27 afterthe closure assembly has been secured to the container 61 and therelationship of such score line segments to the container and the innercap 59. In particular, FIGS. 1"0l3 show how the curved peripheral wall21 secures theclosure assembly to the container 61.

To open the container, the tab 57 is raised to initiate rupture of theline of weakness 27 adjacent the rivet 17. Next, the

user exerts an outward pulling force on the tab 57 to continue severanceof the material of the outer cap 19 along the line of weakness. Suchseverance will continue down one side of the tear strip 29 along thesegment 31 all the way to the outer edge 37 but will terminate short ofthe edge 37 along the other side of the tear strip 29 because theJ-shaped segment 33 does not continue all the way to the edge 37. Theprogressively increased resistance to tearing afforded by the score linesegment 33 provides additional insurance against complete tear out ofthe tear strip 29. The outer cap 19 may then be removed from the innercap 59 as an integral unit. Thereafter, the resilient inner cap 59 canbe utilized as a removable, reusable closure for the container 61.

Although exemplary embodiments of the invention have been shown anddescribed, many changes, modifications, and substitutions may be made byone having ordinary skill in the art without necessarily departing fromthe spirit and scope of this invention.

I claim:

1. An easy opening closure for use on a container having an openingtherein and a container wall around said opening, said closurecomprising:

a cap of sheet material having an end wall for closing the opening ofthe container and a peripheral wall extending generally transverse tothe end wall, said peripheral wall having an outer edge and beingadapted to at least partially surround the wall of the container,

said cap being scored to define a line of weakness extending at leastsubstantially continuously from a first location at least substantiallyat the outer edge of the peripheral wall over a region of the end walland then back generally toward said first location to terminate at asecond location which is spaced from said outer edge of said peripheralwall, said line of weakness defining a tear portion which is partiallyremovable from said cap;

an end portion of said line of weakness adjacent said second locationbeing scored to a lesser depth than another region of said line ofweakness so that said end portion will offer increased resistance torupture of the material of the cap therealong; and i a pull memberjoined to said tear portion. 2. A closure as defined 111 claim 1 whereinthe depth of score of said end portion of said line of weakness isprogressively decreased as said line of weakness extends toward saidsecond location.

3. A closure as defined in claim 1 wherein said second location is onsaid peripheral 'wall and said end portion includes a generally U-shapedportion opening away from said outer edge.

4. An easy opening closure as defined in claim 1 wherein said endportion of said line of weakness includes a curved region.

5. An easy opening container as defined in claim 1 wherein said endportionof said line of weakness terminates at said second location.

6. An easy opening container as defined in claim 1 wherein a region ofsaid line of weakness adjacent said second location is curved away froman adjacent'portion of said outer edge of said peripheral wall.

